Is the substrate important? If you made an accurate model of a human brain in software, in silicon or using water pipes and valves, would it be able to tnink? Would it be conscious? I have no idea.

Me neither but that's why I don't like arguments that say LLM's can't do X because of their substrate, as if that was self-evident. It's like the aliens saying surely humans can't think because they're made of meat.